Not quite sure what you mean by "tap enter" but you could bind a macro to whatever keystroke you feel is handy. You could also probably bind a keystroke to hit the clip library to insert the comment block.
I think what is meant is effectively a pretty advanced form of code snippets. This would mean that once a block comment was started it would continue to create comment marks automatically until stopped.
The only app I have seen that does this is TextMate on Mac OS X. There is a screencast of this in action at http://macromates.com/screencast/scopes ... mments.mov but beware, it is about 61MB. It illustrates how to cause return (↩) to also insert an asterisk when used inside block comments such as:
How about a macro that inserts Blocked Comments from the clip library, selects that blocked section and does a Search for "\n" and replace with "\n *" .
That macro could be assigned a hot key, and could be easily triggered to run when needed.
/* Write your block comments
like this, without a star on
every line? */
It makes it easier to comment and uncomment large blocks of code that way, and the syntax highlighting should already make it fairly obvious what is and isn't a comment, so adding stars is a bit redundant IMO.